Door latch mechanism



Sept. 7, 1965 c. A. BEHRENS 3,204,996

DOOR LATCH MECHANISM Original Filed Dec. 7, 1961 2 Sheets-Sheet 1 BYgam/p V fM m Qfya Sept. 7, 1965 c. A. BEHRENS DOOR LATCH MECHANISM 2Sheets-Sheet 2 Original Filed Dec. 7, 1961 n h H k\% 9 6, 2 w 5 9 w WM0% 0 9 Mk 5 2 4 0 9 9 9 6 9 Q Q m" 9 A C l W f I. [l v A A; 9 9 +7 0 a wd L m m g h w M W I N VEN TOR. B 6/2 Texas M, fM

United States Patent 3,204,996 DOOR LATCH MECHANISM Charles A. Behrens,Sterling, lll., assignor to National Manufacturing Co., Sterling, 11].,a corporation of Illinois Original application Dec. 7, 1961, Ser. No.157,716. Divided and this application Feb. 20, 1963, Ser. No. 259,878

4 Claims. (Cl. 292-341.15)

This application is a division of my co-pending application Serial No.157,716, filed December 7, 1961 and now abandoned.

This invention relates to a door latch mechanism and has to do moreparticularly with a keeper or strike forming a portion of a door latchmechanism.

Strikes for door latch mechanisms are known wherein a strike bar isyieldably urged into operative position by a spring or springs whichpermit the bar to be depressed by the latch when the door is moved toclosed position to thereby permit the latching dog portion of the latchbolt to ride over the bar. Customarily, the bar is formed as a rod witha circular cross-section and is relatively small in diameter in orderthat the latch mechanism may not be unduly large and cumbersome. Such arod is usually rotatable in the casing in which it is carried.Consequently, a strike employing such a rod is subject to thedisadvantage that the latched door can be released by shaking the dooruntil the bar rolls out from behind the latching dog of theybolt.

Prior strike bars of circular cross-section also are subject to thedisadvantage that they may be bent or broken in use unless made undulylarge in diameter.

In many prior strikes, the strike bar is urged into operative positionby a pair of coil springs bearing against opposite ends of the strikebar. When the bar is of conventional form, certain difficulties arise inconnection with suitably positioning the springs relatively to the endsof the bar and in maintaining the springs in the desired positions.

An object of the present invention is to provide a new and improved doorlatch mechanism.

Another object is to provide a new and improved strike for a door latchmechanism.

Another object is to provide a strike for a door latch mechanism of suchconstruction that the latch cannot be disengaged by shaking the door.

Another object is to provide a strike for a door latch mechanism whichhas increased strength over conventional strikes without any increase inoverall dimensions in the direction of the length of the latch bolt. 7Another object is to provide a strike for a door latch of the typewherein the strike bar is yieldably supported by springs at each end ofthe bar and wherein the construction is such that the springs areretained in proper position without being attached to the strike bar.

Another object is to provide a strike for a door latch of the typewherein the strike bar is yieldably supported by springs at each end ofthe bar and wherein the construction is such that no backing plate isrequired for the springs.

Still another object is to provide a novel strike for a door latchmechanism which strike is of very simple construction and can be easilyand inexpensively made and assembled.

Other objects and advantages will appear from the following descriptiontaken in connection with the appended drawings, wherein:

FIGURE 1 is an elevational View of the latch mechanism from the insideof the door;

FIG. 2 is a horizontal sectional view taken along line 22 of FIG. 1;

ice

FIG. 3 is an enlarged front elevational view of the strike shown inFIGS. 1 and 2;

FIG. 4 is a vertical sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a new elevational view of the strike;

FIG. 6 is an enlarged, transverse, sectional View taken along line 6-6of FIG. 4; and

FIG. 7 is an enlarged transverse sectional view taken along line 77 ofFIG. 4.

Referring now particularly to FIGS. 1 and 2, the door 1 is suitablymounted for opening and closing movement and preferably is hinged at theedge opposite the edge carrying the latch. The face edge of the door isadapted to abut against a shoulder 2 formed in the door jamb or frame 3.A strike 4, hereinafter described in detail, is attached to the doorjamb 3 as by screws (not shown) and has a strike bar 90 in position tobe engaged by a latching member or bolt 5 carried by the door.

The latch bolt 5 and its mounting are fully disclosed in my co-pendingapplication S.N. 157,716 and since the details thereof form no part ofthe present invention, it is not disclosed in detail herein. However, itwill be understood that the latch bolt 5 is mounted in a bearing supportmember 25 for both rocking and rotary motion whereby it can be engagedwith the disengaged from the strike bar 90.

The latch bolt 5 is formed with a latching dog 42 having a latchingsurface 43 and forwardly thereof is formed with a notch 44 to insurethat the strike bar 90 will seat behind the surface 43. The dog 42 isprovided with an inclined cam surface 46a for camming down the strikebar 90 as the dog moves into latching position past and beyond thestrike bar 90.

The strike is shown in detail in FIGS. 3 to 7 to which reference is nowmade. It comprises a casing 80, a strike bar 90 and a pair of springs92. The casing includes a base or flange portion 81 having preferably aflat bottom surface 82 adapted to lie against the door frame. The casing80 also includes a socket portion 83 integral with and upstanding fromthe base portion 82 and formed with side walls 84, end walls 85 and atop wall 86. The top wall 86 is provided with an elongate opening 87 andthe side walls 84 are formed with deep notches 88 extending downwardlyfrom the opening 87. Thus, the construction in effect defines a recesswith two sockets 89 at the opposite ends of the casing 80 havingsubstantially parallel inner sidewalls. The remaining portions of theside walls also are generally parallel.

The strike bar 90 is of elongate form and disposed floatingly in therecess within the casing member 80 and is of suflicient length so thatits end portions extend into the sockets 89 to such an extent that thestrike bar 90 cannot be dislodged from the casing member 86 after thedevice has been assembled as hereinafter described and is constrained toslide in the casing member.

The strike bar 90 is of a generally rectangular crosssecti-onal formwherein the transverse dimension in a direction from top to bottom ofthe recess is substantially greater than the other transverse dimension,thereby providing substantially stronger bar than would be provided ifit were circular or other form having equal transverse dimensions. Itwill be noted in this connection that the body portion of the bar havingsuch larger transverse dimension extends into the two end sockets. Theupper edge of the strike bar 90 i convexly shaped to provide a cammingsurface 96 adapted to be engaged by the cam surface 46a of the latchingdog 42 on the latching member 5. The side surfaces of the bar 90 areflat and generally parallel whereby the surface which is positioned tobe engaged by the latching surface 43 of the dog 42 presents asubstantial area for such engagement.

The end portions of the bar 90 are notched and of substantially reduceddimension in the direction of the depth of the sockets and a pair ofcoil springs 92 are provided which abut at their upper ends against theflat faces of the end portions 91. At their inner ends, the springs areretained by spinning or staking the casing member as at 93 whichspinning or staking also provides a back stop against which the springsmay be compressed when the strike bar is depressed. The opposing wallsof each of the sockets 89 are provided with grooves 95 which formenlargements of the sockets to accommodate the springs 92 respectively.

A pair of elongate slots 94 are provided at the ends of base 81 fortemporarily securing the strike to a door jamb or frame to permitadjustment of its position, and a pair 'of screw holes 97 are providedfor permitting screws to be passed through to secure the strike in itsfinal, adjusted position.

The strike operates in a manner generally similar to other strikeshaving depressi'ble strike bars. The strike bar 90 is normally urgedinto its upper position by the springs 92, in which position the centralportion of the bar 90 is exposed and is in position to be engaged by thelatching dog 42. When the door is open, the latchin-g dog is positionedaway from the strike bar 90 and as the door is closed the cam surface46a of the dog 42 engages the curved camming surface 96 of the strikebar 90 and urges the strike bar downwardly out of its normal position bya camming action, so that the latching dog 42 can ride over and past thestrike bar 90. When the dog has cleared thestrike bar 90, the latter isurged into its latching position (FIG. 2) by the springs 92.

In its movement between its latching position and its depressedposition, the strike bar 90 is guided by the generally parallel sidewalls of the recess which are sufliciently close together to preventmaterial tilting or rocking of the strike bar about its longitudinalaxis. Owing to the shape of the strike bar, there is a substantial sideface area adapted to engage the side face of the recess to provide alarge bearing area. Moreover, owing to the shape of the strike bar, ithas a substantial cross section providing substantial stiffness andrigidity.

The reduced or notched ends of the strike bar permit the strike bar tobe depressed to a position wherein its inner face is in the plane of thebottom face of the base 81. Thus the springs 82 can be wholly disposedwithin the casing 80 and they are not damaged in any way by thedepression of the strike bar. In other words, the shape of the ends 91of the strike bar is uch that recesses are provided for receiving thesprings even when the strike bar is in its fully depressed position.

It will be seen that the strike bar is provided with a fiat facepositioned to be engaged by the face 43 of the dog 42 when latchingmember is in its latching position against the strike bar. This featureinsures that the latch cannot be released from the latch bar by shakingthe door to thereby release the door. Thus the shape of the strike barrepresents a substantial improvement over strike bars of circular shapewherein the door can often be opened by shaking the door to cause theround strike bar to roll out from engagement with the latching face ofthe latching member.

I claim:

1. A door latch strike comprising a hollow casing having a base flange,end walls and generally parallel side walls upstanding from saidbaseflange and a top wall 4 joining said side walls at their tops, said end,side and top walls defining a recess open at its bottom, said top wallbeing formed with an opening terminating short of its ends and said sidewalls being notched adjacent said top wall opening, a strike barfloatingly lidable in said recess between :a position against said topwall wherein at least a portion of said bar is exposed and a positiondisplaced therefrom in the direction of said base flange, and meansyieldably urging said bar into position against said top wall, saidstrike bar having a corresponding dimension substantially equal to thewidth of said recess and a transverse dimension which is substantiallygreater in the direction of movement of the strike bar than thedirection transversely thereto and a convexly upper surface atle'ast indoor latch dog having a flat latching surface and a camming surfaceinclined thereto, said strike comprising a hollow casing having a baseflange, end walls and generally parallel side walls upstanding from saidbase flange and a top wall joining said side wall at their tops, saidend, side and top walls defining a recess open at its bottom, said topwall being formed with an opening terminating short of its ends and saidside wall being notched adjacent said top wall opening, a strike barfioatingly slidable in said recess between a position against said topwall wherein at least a portion of said bar is exposed and a positiondisplaced therefrom in a direction toward said base flange, and meansyieldably urging said bar into position against said top wall, said barhaving a flat side wall surface adapted for engagement with said flatdoor latch dog urface, said bar having a corresponding dimensionsubstantially equal to the width of said recess and a convexly curvedupper surface adapted for engagement with said camming surface on saiddoor latch dog.

3. A door latch strike as set forth in claim 1 wherein said meansyieldably urging said bar comprises a pair of coil springs disposed insaid recess and each engaging an end portion of said bar respectively,means retaining said springs in said recess, and said bar being recessedat its ends to receive said springs, whereby when the bottom of said baris flush with the bottom of said casing, said springs are disposedwholly within such recesses in said bar. l 4. A door latch strike as setforth in claim 2 wherein said means yieldably urging said bar comprisesa pair of coil springs freely abutting the lower surfaces of the ends ofsaid strike bar respectively and means entirely within said recess andprojecting inwardly from the rim of said recess adjacent the bottomthereof and engaging the bottoms of said springs for retaining saidsprings in said recess.

References Cited by the Examiner UNITED STATES PATENTS 2,178,919 11/39Rhein 292--34l.15 2,185,503 1/40 Fryer 292341.18 2,583,391 1/52 Quinn292341.15 2,790,668 4/57 Friedman et al. 292--341.15 2,949,328 8/60Kaiser 292228 2,95 6,829 10/60 Gerth 292341.15

ALBERT H. KAMPE, Primary Examiner.

M. HENSON WOOD, 1B,, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Not3,204,996 September 7, 1965 Charles Au Behrens at error appears in theabove numbered pat- It is hereby certified th Letters Patent should readas ent requiring correction and that the said corrected below.

line 25, for "with the" read with and Column 2,

" read convexly curvec' column 4, line 14, for "convexly upper upperSigned and sealed this 26th day of July 1966 (SEAL) Attest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner ofPatents

1. A DOOR LATCH STRIKE COMPRISING A HOLLOW CASING HAVING A BASE FLANGE,END WALLS AND GENERALLY PARALLEL SIDE WALLS UPSTANDING FROM SAID BASEFLANGE AND A TOP WALL JOINING SAID SIDE WALLS AT THEIR TOPS, SAID END,SIDE AND TOP WALLS DEFINING A RECESS OPEN AT ITS BOTTOM, SAID TOP WALLBEING FORMED WITH AN OPENING TERMINATING SHORT OF ITS ENDS AND SAID SIDEWALLS BEING NOTCHED ADJACENT SAID TOP WALL OPENING, A STRIKE BARFLOATINGLY SLIDABLE IN SAID RECESS BETWEEN A POSITION AGAINST SAID TOPWALL WHEREIN AT LEAST A PORTION OF SAID BAR IS EXPOSED AND A POSITIONDISPLACED THEREFROM IN THE DIRECTION OF SAID BASE FLANGE, AND MEANSYIELDABLY URGING SAID BAR INTO POSITION AGAINST SAID TOP WALL, SAIDSTRIKE BAR HAVING A CORRESPONDING DIMENSION SUBSTANTIALLY EQUAL TO THEWIDTH OF SAID RECESS AND A TRANSVERSE DIMENSION WHICH IS SUBSTANTIALLYGREATER IN THE DIREC-